In many types of surgical procedures, it is known to use a suture anchor to hold tissues together. For example, in the field of gastroenterology, suture anchors have been used in enterostomy procedures to hold a portion of a viscus (e.g. the stomach or other abdominal organ) in place against another tissue portion, such as the abdominal wall or another organ. In the case of a gastrostomy, for example, a suture has a sturdy elongated piece (e.g. a thin bar or similar anchor member) that is freely movable attached at or near one end of the suture. A needle is inserted through the abdominal wall and stomach wall, and the elongated piece with the trailing suture is inserted through the needle and into the stomach. The elongated piece is longer than the width of the needle and the hole through the tissue, and so it is unable to be pulled back through the needle or hole unless it is exactly positioned along the hole or needle.
The suture extending through the tissues (and perhaps within the needle) is pulled. The pulling force is transmitted to the elongated piece, which is forced against the interior of the stomach, and pulls a portion of the stomach toward the abdominal wall. Procedures and existing suture anchors are exemplified in U.S. Pat. No. 6,699,263 to Cope, owned by the assignee of the present application and incorporated herein by reference in its entirety. The stomach tissue is pulled against the abdominal wall for ease of insertion of other devices, such as catheters for drainage or administration of therapy. The drawing together creates a seal between the abdominal wall and stomach tissues so as to help prevent fluid traffic between the stomach and abdominal cavity, which may result in peritonitis or other infections or complications involving the stomach or abdominal tissues. In some cases, the suture anchor remains in place for a period of days or weeks so as to ensure a desired engagement and stability between tissues.
One method known to keep the tension on the suture so as to maintain the tissues against each other—the stomach against the abdominal wall in the above example—uses a hemostat or other clamping device to crimp one or more metal crimp beads to the suture outside the patient. Having pulled the stomach toward and against the abdominal wall, the stomach tends to pull back on the elongated piece and suture. The crimped bead(s) hold the suture, ideally preventing it slipping through the hole in the tissue, and in the process the bead(s) are pulled against the patient's skin. While effective, this procedure has certain drawbacks. Patient discomfort and the close work of crimping the bead(s) are among such drawbacks. The size of and potential for pinching or sharp edges can injure or irritate surrounding tissue or enlarge the hole. The pull on the suture forces the bead(s) against the skin, resulting in poking discomfort from a small-surface-area item being pressed against the skin. There is a risk of slippage of the suture within the bead(s), especially if the crimp is initially insufficient. There is also the risk of cutting the suture inadvertently during crimping. Metals used for the bead(s) are generally incompatible with MRI procedures for reviewing the status of the procedure. The small size of the bead(s) and the necessity of accurate placement to ensure maintaining tension without injuring the patient makes for difficult and close work for the surgeon.
Another standard method for maintaining the tissues together is to anchor the free end of the suture in the patient's skin, as by sewing the suture into the skin directly. With at least local anesthetic from the insertion of the suture anchor, additional piercings of the skin to hold the free end of the suture may cause minimal initial discomfort, but discomfort will increase as the duration of the suture anchor in the body extends. With additional skin piercings to fasten the tensioned suture, there is also an increase in the potential for infection or other complications, and thus additional discomfort for the patient and work for the health-care provider,
Accordingly, there remain needs for a suture anchor holding mechanisms that have less risk for discomfort to the patient, especially in cases where the suture anchor needs to remain in the patient for a substantial period of time, and which is easier are use than current techniques.